Such a vacuum cleaner and such a suction tube are known, inter alia from the Japanese Patent Application bearing the application number 63-106340. The vacuum cleaner described in said Japanese Patent Application comprises a suction tube with an optical unit which forms part of the remote control circuit, which optical unit is adapted to detect whether a user of a vacuum cleaner is holding the grip in a hand. For detecting the hand the optical unit comprises a light-emitting part and a light-receiving part, a light beam generated by the light-emitting part and detected by the light-receiving part being interrupted by the hand of a user of the vacuum cleaner. The remote control circuit controls the electronic circuit in response to the detection of the hand, the electric motor being switched on when the hand is detected and being switched off in the absence of the hand. Since the electric motor of the vacuum cleaner is switched on when a user of the vacuum cleaner holds the grip forming part of the suction tube and is switched off when a user of the vacuum cleaner releases the grip forming part of the suction tube the optical unit, which forms part of the remote control circuit, improves the ease of operation of the vacuum cleaner.
A drawback of the known vacuum cleaner is that the optical unit forming part of the remote control circuit is susceptible to faults.